PIEZOELECTRIC/ELECTROSTRICTIVE DEVICE

Abstract

A piezoelectric/electrostrictive device has a rotor substantially in the form of a rectangular parallelepiped, and a rotary actuator for angularly displacing the rotor 12. The rotary actuator includes a stationary member, a first vibratory plate and a second vibratory plate extending in one direction from opposite sides of the stationary member, a first piezoelectric/electrostrictive element for actuating the first vibratory plate, and a second piezoelectric/electrostrictive element for actuating the second vibratory plate. The rotor includes a pair of opposite surfaces, one of the surfaces having a first end secured to an end of the first vibratory plate and a second end, which is diagonally opposite to the first end, and which is secured to an end of the second vibratory plate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing a first piezoelectric/electrostrictive device according to the present invention;

FIG. 2 is a view showing a second piezoelectric/electrostrictive device according to the present invention;

FIG. 3 is a view showing a first modification of the first piezoelectric/electrostrictive device;

FIG. 4 is a view showing a third piezoelectric/electrostrictive device according to the present invention;

FIG. 5 is a view showing a manner in which the third piezoelectric/electrostrictive device operates according to a first process;

FIG. 6 is a view showing a manner in which the third piezoelectric/electrostrictive device operates according to a second process;

FIG. 7 is a view showing a fourth piezoelectric/electrostrictive device according to the present invention;

FIG. 8 is a plan view of a first ceramic substrate of the fourth piezoelectric/electrostrictive device;

FIG. 9 is a plan view of a second ceramic substrate of the fourth piezoelectric/electrostrictive device;

FIG. 10 is a plan view of a third ceramic substrate of the fourth piezoelectric/electrostrictive device;

FIG. 11 is a view showing a fifth piezoelectric/electrostrictive device according to the present invention;

FIG. 12 is a view showing a manner in which the fifth piezoelectric/electrostrictive device operates in a first mode;

FIG. 13 is a view showing a manner in which the fifth piezoelectric/electrostrictive device operates in a second mode;

FIG. 14 is a view showing a first modification of the fifth piezoelectric/electrostrictive device;

FIG. 15 is a view showing a step (punching step) for manufacturing the fifth piezoelectric/electrostrictive device;

FIG. 16 is a view showing a step (bending step) for manufacturing the fifth piezoelectric/electrostrictive device;

FIG. 17 is a view showing a sixth piezoelectric/electrostrictive device according to the present invention;

FIG. 18 is a view showing a manner in which the sixth piezoelectric/electrostrictive device operates;

FIG. 19 is a view showing a step (punching step) for manufacturing the sixth piezoelectric/electrostrictive device;

FIG. 20 is a view showing a step (bending step) for manufacturing the sixth piezoelectric/electrostrictive device;

FIG. 21 is a view showing a first modification of the sixth piezoelectric/electrostrictive device;

FIG. 22 is a view showing a second modification of the sixth piezoelectric/electrostrictive device;

FIG. 23 is a perspective view showing the sixth piezoelectric/electrostrictive device with a rotor fixed to a rotary actuator;

FIG. 24 is a view showing a step (punching step) for manufacturing the second modification of the sixth piezoelectric/electrostrictive device;

FIG. 25 is a view showing a step (bending step) for manufacturing the second modification of the sixth piezoelectric/electrostrictive device;

FIG. 26 is a perspective view of a seventh piezoelectric/electrostrictive device according to the present invention;

FIG. 27 is a plan view of a first modification of the seventh piezoelectric/electrostrictive device;

FIG. 28 is a plan view of a second modification of the seventh piezoelectric/electrostrictive device;

FIG. 29 is a plan view of a third modification of the seventh piezoelectric/electrostrictive device;

FIG. 30 is a plan view of a fourth modification of the seventh piezoelectric/electrostrictive device;

FIG. 31 is a plan view of a fifth modification of the seventh piezoelectric/electrostrictive device;

FIG. 32 is a view showing an eighth piezoelectric/electrostrictive device according to the present invention;

FIG. 33 is a view of a first modification of the eighth piezoelectric/electrostrictive device;

FIG. 34 is a view of a second modification of the eighth piezoelectric/electrostrictive device;

FIG. 35 is a view showing a ninth piezoelectric/electrostrictive device according to the present invention;

FIG. 36 is a view showing a tenth piezoelectric/electrostrictive device according to the present invention;

FIG. 37 is a view of a first modification of the tenth piezoelectric/electrostrictive device;

FIG. 38 is a view of a second modification of the tenth piezoelectric/electrostrictive device;

FIG. 39 is a view showing a step (punching step) for manufacturing the second modification of the tenth piezoelectric/electrostrictive device;

FIG. 40 is a view showing a step (rotary actuator fabricating step) for manufacturing the second modification of the tenth piezoelectric/electrostrictive device;

FIG. 41 is a view showing a step (adhesive applying step) for manufacturing the second modification of the tenth piezoelectric/electrostrictive device;

FIG. 42 is a view showing a step (assembling step) for manufacturing the second modification of the tenth piezoelectric/electrostrictive device;

FIG. 43 is a view showing a step (adhesive applying step) for manufacturing the second modification of the tenth piezoelectric/electrostrictive device;

FIG. 44 is a view showing a step (parts mounting step) for manufacturing the second modification of the tenth piezoelectric/electrostrictive device;

FIG. 45 is a view showing another step used in manufacturing the second modification of the tenth piezoelectric/electrostrictive device;

FIG. 46 is a view showing an eleventh piezoelectric/electrostrictive device according to the present invention; and

FIG. 47 is a view showing a modification of the eleventh piezoelectric/electrostrictive device.

Claims

1. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a stationary member, with a first vibratory plate and a second vibratory plate extending in one direction from opposite sides of said stationary member, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates; andsaid rotor having a pair of opposite surfaces, one of said opposite surfaces including a first end secured to said first vibratory plate, and the other of said opposite surfaces having a second end, which is diagonally opposite to said first end, secured to said second vibratory plate.

2. A piezoelectric/electrostrictive device according to claim 1, wherein the distance between said first end of said rotor that is secured to said first vibratory plate and a boundary region between said first vibratory plate and said stationary member is represented by L1, and the distance between said second end of said rotor that is secured to said second vibratory plate and a boundary region between said second vibratory plate and said stationary member is represented by L2, wherein said distance L1 and said distance L2 satisfy the relationship L1=L2.

3. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a first stationary member and a second stationary member which are spaced from each other, a first vibratory plate extending in one direction from one side of said first stationary member, a second vibratory plate extending in one direction from one side of said second stationary member, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates; andsaid rotor having a pair of opposite surfaces, one of said opposite surfaces including a first end secured to said first vibratory plate, and the other of said opposite surfaces having a second end, which is diagonally opposite to said first end, secured to said second vibratory plate.

4. A piezoelectric/electrostrictive device according to claim 3, wherein said first vibratory plate has a first protrusion mounted on a surface thereof which faces said one surface of said rotor; said second vibratory plate has a second protrusion mounted on a surface thereof which faces said other surface of said rotor;said first protrusion and said one surface of said rotor are secured to each other; andsaid second protrusion and said other surface of said rotor are secured to each other.

5. A piezoelectric/electrostrictive device according to claim 3, wherein said first stationary member has a third protrusion mounted on a surface thereof which faces said rotor; said second stationary member has a fourth protrusion mounted on a surface thereof which faces said rotor;said third protrusion and said rotor are secured to each other; andsaid fourth protrusion and said rotor are secured to each other.

6. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a central member extending in a first direction, a first arm extending from a first end of said central member in a second direction, a second arm extending from a second end of said central member in a third direction which is opposite to said second direction, a first vibratory plate extending from an end of said first arm in said first direction, a third arm extending from an end of said first vibratory plate in said third direction, a second vibratory plate extending from an end of said second arm in said first direction, a fourth arm extending from an end of said second vibratory plate in said second direction, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates.

7. A piezoelectric/electrostrictive device according to claim 6, wherein said central member comprises a stationary member; and said rotor has, on a principal surface thereof, a first corner secured to said third arm and a second corner, which is diagonally opposite to said first corner, secured to said fourth arm.

8. A piezoelectric/electrostrictive device according to claim 6, wherein each of said third arm and said fourth arm comprises a stationary member; and said rotor is secured to said central member.

9. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a first stationary member and a second stationary member which are spaced from each other, a central member disposed between said first stationary member and said second stationary member and extending in a first direction, a first vibratory plate extending from a first end of said first stationary member toward said second stationary member, a second vibratory plate extending from a second end, which is diagonally opposite to said first end, of said second stationary member toward said first stationary member, a first displacement transmitter connected between a third end, which is closer to said first stationary member, of said central member on a surface thereof which faces said first vibratory plate, and an end of said first vibratory plate, for transmitting displacement of said first vibratory plate to said central member, a second displacement transmitter connected between a fourth end, which is closer to said second stationary member, of said central member on a surface thereof which faces said second vibratory plate, and an end of said second vibratory plate, for transmitting displacement of said second vibratory plate to said central member, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates; andsaid rotor being secured to said central member.

10. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a first stationary member and a second stationary member which are spaced from each other, a first metal vibratory plate extending from said first stationary member toward said second stationary member, a second metal vibratory plate extending from said second stationary member toward said first stationary member, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates; andsaid rotor having a pair of opposite surfaces, one of said opposite surfaces having a first end secured to said first vibratory plate, and the other of said opposite surfaces having a second end, which is diagonally opposite to said first end, secured to said second vibratory plate.

11. A piezoelectric/electrostrictive device according to claim 10, wherein said first stationary member and said second stationary member are integrally combined with each other by a frame.

12. A piezoelectric/electrostrictive device according to claim 10, wherein said first stationary member, said first vibratory plate, said second stationary member, and said second vibratory plate are formed by punching and bending a single metal plate.

13. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a first stationary member and a second stationary member which are spaced from each other, a first metal vibratory plate extending from said first stationary member toward said second stationary member, a second metal vibratory plate extending from said second stationary member toward said first stationary member, a rotor mount secured to an end of said first vibratory plate and to an end of said second vibratory plate, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates; andsaid rotor being mounted on said rotor mount.

14. A piezoelectric/electrostrictive device according to claim 13, wherein said first stationary member and said second stationary member are integrally combined with each other by a frame.

15. A piezoelectric/electrostrictive device according to claim 13, wherein said first stationary member, said first vibratory plate, said second stationary member, said second vibratory plate, and said rotor mount are formed by punching and bending a single metal plate.

16. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a stationary member, a first metal vibratory plate having an end secured to said stationary member and extending in one direction, a second metal vibratory plate having an end secured to said stationary member and extending along an extension of said first vibratory plate, a third metal vibratory plate having an end secured to said stationary member, said third vibratory plate being spaced from said first vibratory plate and extending substantially parallel thereto, a fourth metal vibratory plate having an end secured to said stationary member and extending along an extension of said third vibratory plate, and a piezoelectric/electrostrictive element mounted on at least one of said first through fourth vibratory plates for actuating said at least one of said first through fourth vibratory plates; andsaid rotor having a pair of opposite surfaces, one of said opposite surfaces having a first end secured to said first vibratory plate, and the other of said opposite surfaces having a second end, which is diagonally opposite to said first end, secured to said fourth vibratory plate.

17. A piezoelectric/electrostrictive device according to claim 16, wherein said stationary member comprises a frame; said first vibratory plate and said second vibratory plate are secured to a first arm extending from one of two opposite surfaces of said frame to the other surface thereof; andsaid third vibratory plate and said fourth vibratory plate are secured to a second arm extending from said other surface of said frame to said one surface thereof.

18. A piezoelectric/electrostrictive device according to claim 16, wherein said stationary member has a rectangular planar shape; said first vibratory plate and said second vibratory plate are secured to a first arm extending upwardly from one of two opposite surfaces of said stationary member; andsaid third vibratory plate and said fourth vibratory plate are secured to a second arm extending upwardly from the other of said two opposite surfaces of said stationary member.

19. A piezoelectric/electrostrictive device according to claim 16, wherein said stationary member and said first through fourth vibratory plates are formed by punching and bending a single metal plate.

20. A piezoelectric/electrostrictive device according to claim 16, wherein those of said first through fourth vibratory plates which are free of said piezoelectric/electrostrictive element comprise a spring.

21. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a stationary member, a first metal vibratory plate having an end secured to said stationary member and extending in one direction, a second metal vibratory plate having an end secured to said stationary member and extending along an extension of said first vibratory plate, a third metal vibratory plate having an end secured to said stationary member, said third vibratory plate being spaced from said first vibratory plate and extending substantially parallel thereto, a fourth metal vibratory plate having an end secured to said stationary member and extending along an extension of said third vibratory plate, a rotor mount secured to respective ends of said first through fourth vibratory plates, and a piezoelectric/electrostrictive element mounted on at least one of said first through fourth vibratory plates for actuating said at least one of said first through fourth vibratory plates; andsaid rotor being mounted on said rotor mount.

22. A piezoelectric/electrostrictive device according to claim 21, wherein said stationary member comprises a frame; said first vibratory plate and said second vibratory plate are secured to a first arm extending from one of two opposite surfaces of said frame to the other surface thereof; andsaid third vibratory plate and said fourth vibratory plate are secured to a second arm extending from said other surface of said frame to said one surface thereof.

23. A piezoelectric/electrostrictive device according to claim 21, wherein said stationary member has a rectangular planar shape; said first vibratory plate and said second vibratory plate are secured to a first arm extending upwardly from one of two opposite surfaces of said stationary member; andsaid third vibratory plate and said fourth vibratory plate are secured to a second arm extending upwardly from the other of said two opposite surfaces of said stationary member.

24. A piezoelectric/electrostrictive device according to claim 21, wherein said rotor mount comprises a plurality of feet fixed to respective ends of said first through fourth vibratory plates.

25. A piezoelectric/electrostrictive device according to claim 21, wherein said stationary member, said first through fourth vibratory plates, and said rotor mount are formed by punching and bending a single metal plate.

26. A piezoelectric/electrostrictive device according to claim 21, wherein those of said first through fourth vibratory plates which are free of said piezoelectric/electrostrictive element comprise a spring.

27. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a stationary member, with a first vibratory plate and a second vibratory plate having respective ends secured to said stationary member and which are angularly spaced from each other by a predetermined angle, a movable member connected between another end of said first vibratory plate and another end of said second vibratory plate, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates; andsaid rotor being secured to said movable member.

28. A piezoelectric/electrostrictive device according to claim 27, wherein said predetermined angle comprises an acute angle.

29. A piezoelectric/electrostrictive device according to claim 27, wherein said predetermined angle comprises an obtuse angle.

30. A piezoelectric/electrostrictive device according to claim 27, wherein said predetermined angle is 90 degrees.

31. A piezoelectric/electrostrictive device according to claim 27, wherein said predetermined angle is 180 degrees.

32. A piezoelectric/electrostrictive device comprising: a rotor; anda rotary actuator for angularly displacing said rotor;said rotary actuator having a stationary member, with a first vibratory plate and a second vibratory plate extending in one direction from opposite sides of said stationary member, and a piezoelectric/electrostrictive element mounted on at least one of said first and second vibratory plates for actuating said at least one of said first and second vibratory plates; andsaid rotor having a first connector extending from a first portion thereof, which faces said first vibratory plate, to said first vibratory plate, said first connector interconnecting said first portion and said first vibratory plate, and a second connector extending from a second portion thereof, which faces said second vibratory plate, to said second vibratory plate, said second connector interconnecting said second portion and said second vibratory plate.

33. A piezoelectric/electrostrictive device according to claim 32, wherein said rotor has a constricted portion; said first portion is positioned on said constricted portion, which faces said first vibratory plate; andsaid second portion is positioned on said constricted portion, which faces said second vibratory plate.

34. A piezoelectric/electrostrictive device according to claim 33, wherein said first connector is of a shape having a cross-sectional area that is substantially uniform from said constricted portion to said first vibratory plate; and said second connector is of a shape having a cross-sectional area that is substantially uniform from said constricted portion to said second vibratory plate.

35. A piezoelectric/electrostrictive device according to claim 33, wherein said first connector is of a shape having a cross-sectional area that progressively varies from said constricted portion to said first vibratory plate; and said second connector is of a shape having a cross-sectional area that progressively varies from said constricted portion to said second vibratory plate.

36. A piezoelectric/electrostrictive device according to claim 32, wherein said first connector and said first vibratory plate are secured to each other by an adhesive; and said second connector and said second vibratory plate are secured to each other by an adhesive.

37. A piezoelectric/electrostrictive device according to claim 32, wherein said first connector and said second connector are formed integrally with said rotor, said first vibratory plate, and said second vibratory plate by punching and bending a metal plate.

38. A piezoelectric/electrostrictive device according to claim 32, wherein a first joint position between said first connector and said first vibratory plate, and a second joint position between said second connector and said second vibratory plate, are in a substantially confronting positional relationship.

39. A piezoelectric/electrostrictive device according to claim 32, wherein a third joint position between said first portion of said rotor and said first connector, and a fourth joint position between said second portion of said rotor and said second connector, are positionally related to each other in point symmetry with respect to a center of gravity of said rotor.